Non-pneumatic wheel constructions and their benefits are described in e.g., U.S. Pat. Nos. 6,769,465; 6,994,134; 7,013,939; and 7,201,194, which are incorporated herein by reference in their entirety. Some non-pneumatic tire constructions propose incorporating a shear band, embodiments of which are described in e.g., U.S. Pat. Nos. 6,769,465 and 7,201,194. Such non-pneumatic tires provide advantages in tire performance without relying upon a gas inflation pressure for support of the loads applied to the tire.
In one example of a non-pneumatic wheel, a compliant band with a ground contacting portion can be connected with a plurality of tension-transmitting, web-like elements (i.e. spokes) extending radially from a center element or hub. For certain constructions, such non-pneumatic wheel may be formed by open cast molding in which a material such as e.g., polyurethane is poured into a mold that forms all or part of the non-pneumatic tire. One or more inextensible reinforcement structures such as cords may be molded in place in the compliant band.
Typically, in such prior constructions, the spokes and the hub are molded as an integral, single-piece construction. Alternatively, the spokes may be integrally joined by a band that is then joined with a hub or wheel center. In either construction, the spokes are not readily removable from either the radially-outer end attached with the compliant band or the radially inner end attached to the hub or wheel center.
The construction of the spokes can affect the performance of the non-pneumatic wheel. Spokes constructed from different sizes, configurations, and materials of construction can affect the way tension is transmitted between the wheel hub and the compliant band, leading to differences in load carry capabilities of the non-pneumatic wheel and perceived handling characteristics. The density of the spokes can also determine e.g., how much tension each spoke carries as it rotates to the top of the wheel during operation.
Because of e.g., the integral construction, prior non-pneumatic wheel constructions are not readily amenable to substituting different spokes into the non-pneumatic wheel. Such a substitution would require destructive steps to cut or extricate both ends of the spoke from the wheel. Additionally, because the spokes are joined or attached with the wheel hub, the substitution of different wheels hubs of different materials or configuration is not readily feasible. Finally, prior manufacturing methods have not been conducive to incorporating reinforcements, shapes, layers of material, and other features into the construction of the spoke.
Accordingly, a spoke for a non-pneumatic wheel that can be more readily molded with reinforcements, various shapes, one or more layers of material, and other features would be useful. Such a spoke that can be readily incorporated into a non-pneumatic wheel without integral construction with the wheel hub would also be beneficial. A spoke that can be more readily connected and disconnected from the wheel hub, the compliant band, or both, would also be useful. A method of manufacturing such a wheel spoke would also be beneficial.